I have been reading up on ammo for my Glock 23 which will be used for defense in the woods. I always thought the 180gr was best for close encounters with attacking animals such as bears or mountain lions. But I ran into this article which really doesn't say what is best for my situation but does feel 180gr is probably not the best choice. After reading it, I got to thinking it may be right. But then, I don't totally trust what one person feels and sometimes numbers don't mean a thing in real life. What do you think?

Why the 180gr Bullet is a Bad Choice for .40 S&W
The original design of the .40S&W cartridge called for a one hundred and eighty grain (180gr) bullet pushed down a barrel with a 1-in-16 twist to a muzzle velocity between 950 and 980 feet per second (fps). This matched the "FBI Lite" or "medium velocity" 10mm loads that were becoming popular at that time.

However, in the years that followed, experience and experiment have shown that the standard 180gr bullet weight is not the best choice for .40S&W handguns. Because of the relatively small cartridge case and long bullet, this particular combination does not maximize the .40ís potential.

The official industry pressure specification for .40S&W is 35,000 pounds per square inch, just like the 9mm.
THE CASE OF THE CASES

A 10mm brass case is approximately 0.992" long, while new .40 brass is only 0.850" long; the difference is 0.142 inches. Since the size of the 180gr bullet remains constant, there is significantly less space inside the .40S&W case than the 10mm case when loaded. That means thereís much less room for error, since pressures build more quickly in that small space. Also, the 10mm was designed for a peak mean pressure higher than the .40 Ö which means the 10mm brass is engineered to handle greater pressure than the .40 case.
CAN'T TAKE THE PRESSURE?

As mentioned above, the .40S&W was never intended to be a high-pressure round like the .357 Magnum, 10mm, or 357SIG. In fact, the SAAMI (Sporting Arms and Ammunition Manufacturers Institute) specification for the .40S&W is the same as the 9mm spec (35kpsi). Furthermore, there is no such thing as "+p" ammunition for the .40S&W. Manufacturers claiming to produce "+p" .40S&W ammunition are either lying (the ammo is really within standard pressure allowances) or taking risks with your life. Using ammunition rated over SAAMI spec in a .40S&W handgun is very dangerous and should not be attempted.

However, because of the deep-seated 180gr bullets, there is very little extra case volume left after powder and bullet are added to the case. Even the smallest variation in bullet seating or powder volume drastically affects the volume of space inside the case where the chemical reaction occurs which builds the pressure which sends the bullet down the barrel. These minor variations, therefore, make it very easy to get an overpressure situation with a 180gr bullet. The table below shows how dramatically peak pressures increase when the bullet is seated too deeply.

Standard OAL for the .40S&W is 1.120" ... table data from "Handloading" by Charles E. Petty, American Handgunner Jan/Feb 1998, p41.
THE MANUFACTURERS KNOW THIS

For this reason, most factory .40S&W 180gr ammunition is loaded a little on the weak side. In order to keep a given load below SAAMI specification for mean pressure, the rounds have to be loaded below their optimal performance level. Why? Because factory ammo is subject to these same minor variations. If companies produced ammunition which was, on average, maximum pressure, every once and a while a round would be significantly OVER pressure. Because such over pressure rounds are unacceptable, the average round has to be "dropped down" a notch in power so there is a wider envelope of safe operation.

This "reduced power" problem is easily seen when the 180gr .40 is compared to the 165gr bullets in the same caliber. While experience tells us that, for any particular caliber and pressure standard, heavier bullets have more momentum (as measured by an IPSC Power Factor) than lighter bullets, this is not the case for the .40S&W Ė an average 180gr load moves at around 975fps and as a PF of 175.5; an average 165gr load at 1,130fps has a PF of 186.5, a VERY big difference denoting significantly greater momentum (as well as energy).

As a side note, the full-power 165gr .40S&W has about the same momentum as most factory .45ACP ammunition out of a barrel of the same length.
A TWIST IN THE STORY

Rate of twist affects how quickly the bullet spins as it leaves the barrel. A 1-in-16 twist means that the bullet will spin one full rotation in 16 inches. So, a 1-in-14 twist (bullet rotates once in 14 inches) is "faster" than 1-in-16. Barrels are designed this way because bullets are spin stabilized, just like a football when you throw a good spiral.

Some folks in the ammunition industry have mentioned to me that one problem with the .40 and 180gr bullets is related to the 1-in-16 barrel twist used in these guns. The experts have been able to perform their own tests with alternative barrels and, with the 180gr bullets, have achieved greater accuracy and velocity (one source safely and consistently made around 1,050fps with a 180gr bullet with a 1-in-14 twist) when using something other than the 1-in-16.
THE kB! PHENOMENON

Another bit of evidence pointing toward the mismatch of .40S&W and the 180gr bullet comes from Dean Speirís extensive research into the kB! ("kaboom") phenomenon, especially with Glock handguns. Due to their partially unsupported chambers, .40S&W Glocks tend to work the web of brass cases more than usual. Constant reworking of the brass by reloaders (who put the brass through a cycle of expansion and resizing each time) weakens the web.

According to Mr. Speir, the vast majority of kB!ís reported with .40S&W handguns have occurred when firing 180gr bullets.

So here you have a chamber design which is not as supportive as it could be, and a load (the full power 180gr .40) which has a tendency towards major pressure fluctuations. Add to this mix brass which has been aged prematurely due to the extra work at the web and itís easy to see that a particularly unlucky brass could be the unlucky home of one of the high-end pressure spikes and result in a kB!

For more information about the kB! phenomenon, see The kB! FAQ located at at this site.
MY ADVICE AND PREDICTION

Most manufacturers have begun producing 165gr loads for the .40S&W now. While some load them light for "reduced recoil" (such as Federalís 165gr HydraShok and Speerís 165gr Gold Dot), other companies are squeezing the maximum potential from the bullet by pushing it to the neighborhood of 1,100 to 1,150fps out of a standard 4" barrel. As mentioned above, this results in more momentum and energy downrange as well as less risk of pressure fluctuations. And because of the reduced variation in pressure, 165gr loads tend to be the most accurate in .40S&W handguns, as well.

In my humble opinion, the 165gr is the proper choice for people who normally choose the "slow and heavy" bullets for defensive use. The FBI apparently agrees, as they broke their long standing tradition of using the heaviest bullets available when they approved two .40S&W rounds for use by agents, both of them 165 grainers.

The 165gr is really the optimum choice for .40S&W shooters. It tends to be more accurate, have greater muzzle energy and momentum, and it significantly reduces the dangers associated with possible bullet setback (a bullet can, through normal handling, seat itself more deeply just by being loaded into the chamber of a gun, etc). I think you'll see the 180gr loads become less and less popular as time goes on, and within a few years the 165gr will be the standard for the .40S&W, while the 180gr will be all but extinct.

You are overthinking it. You are not going to be attacked by a Bear and if you are attacked by a Mt Lion, you will not see it coming. In the extremely unlikely event that you ever need to draw your glock, you will be using it point blank and the bullet you use will not matter much.
Opt for the lighter bullets, cuz your Glock will just be dead-weight while hunting....

AAShooter

11-26-2012 11:37 AM

The one that operates most reliably in the gun?

trooper357

11-26-2012 11:59 AM

Quote:

Originally Posted by AAShooter
(Post 9793853)

The one that operates most reliably in the gun?

^ that was my thought.

mjmagee67

11-26-2012 1:20 PM

Having loaded up every weight of bullet you talked about, I prefer the 180gr being pushed down the tube by 6.7gr. of Power Pistol giving me around 980fps or 176PF. With a little extra powder you can easily hit a PF of180+. The lighter bullets all shot fine but there was a much more noticeable recoil, more of a crack with the lighter bullets and a thump with the heavier bullets. For punching paper at the range I've gone to 6.0gr PP.

The small difference in the PF is probably only on paper. I don't think if you were to shoot someone they are going to shake it off because your PF was down a few points!

Looking to the government for good guidance on anything will more often than not get you in trouble.

Rocklin ehh?

Wildeman_13

11-26-2012 1:27 PM

My XD .40 loves 180gr. It does well on 165gr, but does NOT like anything less than 165gr. As in I ran a box of 155/150gr (I don't recall which it was) and had two fail to feeds and a stove pipe. This is after ~2000 rounds.

I second AAShooter in that you should run a couple of boxes of different grains and see which holds a better pattern for you. And then make sure that your SD choice of bullets works the same at that bullet weight. I think it was a Winchester brand of hollow points at 165gr that shot completely different out of my XD than a box of 165gr Winchester ball.

trooper357

11-26-2012 4:01 PM

I do have a box of 180 and also 165. I get my Glock 23 thursday so I will shoot a box of each and see what the best outcome is. Like I said, Numbers equal the 165 like the article reads but I am more of a seat of the pants person so what ever feel good and preforms the best is what I will carry. I just found it interesting that the writer felt 165 was better than the 180. I was under the impression that the .40S&W Glock liked the 180 and not the 165? But I am a Glock newbee so still getting educated.

MIAMIbaseballer

11-27-2012 3:44 AM

Quote:

Originally Posted by trooper357
(Post 9795427)

I do have a box of 180 and also 165. I get my Glock 23 thursday so I will shoot a box of each and see what the best outcome is. Like I said, Numbers equal the 165 like the article reads but I am more of a seat of the pants person so what ever feel good and preforms the best is what I will carry. I just found it interesting that the writer felt 165 was better than the 180. I was under the impression that the .40S&W Glock liked the 180 and not the 165? But I am a Glock newbee so still getting educated.

I load 180gr bullets almost exclusively in 10mm and 40S&W, they work fine in both calibers.

I think you will get better Muzzle Energy (not to be confused with Power Factor) from a 165gr bullet when loading 40S&W. In general, with pistol calibers, you get more muzzle energy as you go lighter because velocity plays an outsized role in this calculation (unlike PF where bullet weight has equal weight with velocity). Muzzle energy is not the be all end all as bullet weight plays a roll in penetration and heavier is usually better in that capacity. These relationships are not linear and there is usually a sweet spot on the curve for any given loading.

As far as all that case head support nonsense with Glocks, if you load your rounds to published maximums, you will not have a problem in any bullet weight you might buy. I load .45 Super for my G21 using the stock barrel (one of the worst for lack of case head support in a current generation Glock) and have not even had a smile until well past Hodgdon maximums for Longshot.

My advice as far as bullet weight for your 40, get what is on sale and use powder manufacturer load data.

BajaJames83

11-27-2012 7:41 AM

Man I have mounds of 180gr HST!
I guess it all needs to go....

Munk

11-27-2012 4:23 PM

I use 165grn plated bullets sitting on a nearly full case of bluedot (just barely compressed, but even with heavy compression bluedot handles well). It cycles my beretta's brigadier slide without issue. I'd probably not run anything lighter while using bluedot, but i'd gladly go heavier.

I went through a similar thought process when I started reloading .40S&W and saw how much of the case was occupied by a 180gr bullet. Well, actually, I first got thinking in that direction when I noticed notably stronger recoil from Fiocchi 165gr JHP than from the Fed Champion 180gr FMJ. But then, I shot some Rem 180gr JHP, and it also produced a stronger recoil.

On the other hand, Hodgdon is comfortable quoting 1159 fps for the 180gr XTP driven by 8gr of Longshot at 1.125" COAL at 32,300 psi.

robert101

11-28-2012 3:40 PM

I tend to ignore the power factor numbers when going to a heavier bullet. Typically, the increased weight will result in deeper penetration. Yes, there are exceptions but in the 40 S&W and loaded to hot loads, I believe the heavier bullet will provide the best penetration from the .40 cal handgun. In reality, there isn't much difference between them in a handgun becuase we aren't talking about much of a difference in velocity like a rifle round.

trooper357

12-04-2012 3:09 PM

I contacted MagTech who makes a 40PS which is a 180gr .40cal FMJ FN that has a velocity of 1050 fps and energy of 442 lb. Price runs from around $18 to $20 for a box of 50. Problem is they are all sold out everywhere and not in production until next February. But it sounds like a good fit for protection in the woods for me and my G23.

mif_slim

12-04-2012 4:51 PM

I like 180 because it gets me right in the boardline minor/major power factor. :)

bruceflinch

12-04-2012 5:31 PM

I've shot 200 gr bullets for years in my Para .40. Never had an issue.

trooper357

12-07-2012 2:52 PM

Quote:

Originally Posted by mif_slim
(Post 9852237)

I like 180 because it gets me right in the boardline minor/major power factor. :)

I found some MagTech 40PS 180gr after searching for a few days. Seems everyone had it on backorder except one place so I got 5 boxes ordered. It looks like it may be a good fit for me in the woods and 250 rounds will give me some feeling for it. Has good velocity and energy for a 180gr. Lots of others were below 1000 and 400 but I wanted a little more so bought them.